Abstract: A method for starting an electric motor, the motor having a main machine, exciter, and permanent magnet generator (PMG), each having a stator and a rotor, with each rotor mounted to a common shaft, the method comprising starting the main machine in an asynchronous mode by applying a starting current to the stator of the main machine to induce a damper current in a damper winding of the main rotor to generate a starting torque that initiates the rotation of the common shaft, and then running the main machine in synchronous mode by supplying running current from the exciter rotor to the main machine rotor.

Abstract: An alternating current (AC) generator of the type used in vehicular applications and driven by the vehicle engine has a stator winding and a field winding wherein the electrical resistance of the field winding varies as a function of temperature. An exciting current intermittently is allowed to flow through the field winding which induces a current in the stator winding. The output of the stator is rectified and used to charge the vehicle battery. The invention comprises inclusion of field winding current compensation apparatus which varies as a function of temperature to reduce undesired field winding current variations due to temperature which results in improvements of power output and stabilized generator driving torque.

Abstract: In known generators and motors a regulator circuit connected in series with the exciter winding creates too much resistance to allow self-excitation to start at very low speeds. The regulator circuit is therefore shunted by a positive temperature coefficient resistor. This has very low resistance at low temperatures causing sufficient current flow through the exciter winding even at low speeds.